package com.atguigu.flink.chapter05.transform;

import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.datastream.ConnectedStreams;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.co.CoMapFunction;

/**
 * @Author lzc
 * @Date 2023/6/19 13:47
 */
public class ConnectDemo {
    public static void main(String[] args) {
        Configuration conf = new Configuration();
        conf.setInteger("rest.port", 2000);
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment(conf);
        env.setParallelism(1);
        DataStreamSource<Integer> stream1 = env.fromElements(1, 2, 3, 4, 5);
        DataStreamSource<String> stream2 = env.fromElements("a", "b", "c");
        
        ConnectedStreams<Integer, String> cs = stream1.connect(stream2);
        
    
        
        SingleOutputStreamOperator<String> s3 = cs
            .map(new CoMapFunction<Integer, String, String>() {
                @Override
                public String map1(Integer value) throws Exception {
                    return value + ">";
                }
                
                @Override
                public String map2(String value) throws Exception {
                    return value + "<";
                }
            });
        s3.print();
        
        
        try {
            env.execute();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
/*
Connect:
    把两个流和并成一个流, 而且这两个流的类型可以不一致
    
    1. 只能两个流进行合并
    2. 两个流的类型可以不一致
 */